/*
 * Copyright 2013 The Netty Project
 *
 * The Netty Project licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */

package io.netty.util.concurrent;

import java.util.concurrent.TimeUnit;

/**
 * A skeletal {@link Future} implementation which represents a {@link Future} which has been
 * completed already.
 */
public abstract class CompleteFuture<V> extends AbstractFuture<V> {

  private final EventExecutor executor;

  /**
   * Creates a new instance.
   *
   * @param executor the {@link EventExecutor} associated with this future
   */
  protected CompleteFuture(EventExecutor executor) {
    this.executor = executor;
  }

  /**
   * Return the {@link EventExecutor} which is used by this {@link CompleteFuture}.
   */
  protected EventExecutor executor() {
    return executor;
  }

  @Override
  public Future<V> addListener(GenericFutureListener<? extends Future<? super V>> listener) {
    if (listener == null) {
      throw new NullPointerException("listener");
    }
    DefaultPromise.notifyListener(executor(), this, listener);
    return this;
  }

  @Override
  public Future<V> addListeners(GenericFutureListener<? extends Future<? super V>>... listeners) {
    if (listeners == null) {
      throw new NullPointerException("listeners");
    }
    for (GenericFutureListener<? extends Future<? super V>> l : listeners) {
      if (l == null) {
        break;
      }
      DefaultPromise.notifyListener(executor(), this, l);
    }
    return this;
  }

  @Override
  public Future<V> removeListener(GenericFutureListener<? extends Future<? super V>> listener) {
    // NOOP
    return this;
  }

  @Override
  public Future<V> removeListeners(
      GenericFutureListener<? extends Future<? super V>>... listeners) {
    // NOOP
    return this;
  }

  @Override
  public Future<V> await() throws InterruptedException {
    if (Thread.interrupted()) {
      throw new InterruptedException();
    }
    return this;
  }

  @Override
  public boolean await(long timeout, TimeUnit unit) throws InterruptedException {
    if (Thread.interrupted()) {
      throw new InterruptedException();
    }
    return true;
  }

  @Override
  public Future<V> sync() throws InterruptedException {
    return this;
  }

  @Override
  public Future<V> syncUninterruptibly() {
    return this;
  }

  @Override
  public boolean await(long timeoutMillis) throws InterruptedException {
    if (Thread.interrupted()) {
      throw new InterruptedException();
    }
    return true;
  }

  @Override
  public Future<V> awaitUninterruptibly() {
    return this;
  }

  @Override
  public boolean awaitUninterruptibly(long timeout, TimeUnit unit) {
    return true;
  }

  @Override
  public boolean awaitUninterruptibly(long timeoutMillis) {
    return true;
  }

  @Override
  public boolean isDone() {
    return true;
  }

  @Override
  public boolean isCancellable() {
    return false;
  }

  @Override
  public boolean isCancelled() {
    return false;
  }

  /**
   * {@inheritDoc}
   *
   * @param mayInterruptIfRunning this value has no effect in this implementation.
   */
  @Override
  public boolean cancel(boolean mayInterruptIfRunning) {
    return false;
  }
}
